Ignition point assembly



Oct. 2, 1951 Filed March 17, 1948 QTTaRA EKS.

Patented Oct. 2, 1951 UNITED STATES PATENT OFFICE Claims.

The present invention relates generally to distributors for automobile and other gasoline engines, and more particularly to self-cleaning ignition points for distributors.

An object of the present invention is to provide novel ignition points which are self-cleaning during use.

Another object is to provide novel ignition points which are so constructed and mounted that the normally stationary point is rotated or rocked while the movable point is in contact therewith to clean the points during the use thereof and to maintain the contacting surfaces of the points smooth to insure full area contact thereof, thereby eliminating oxidizing, pitting, and other damage to the points, and insuring long life and trouble-free contact.

Another object is to provide novel ignition points which incorporate an adjustable rubbing or fibre block for establishing and maintaining the gap between the ignition points.

Another object is to provide a novel method of automatically cleaning ignition points.

Another object is to provide ignition points which are formed for self-cleaning through the rotation or rocking of the normally stationary point, and in which the rubbing 0r fibre block for the movable point may be synchronized with the rocking movement of the normally stationary point in order to equalize wear on the points and on the rubbing block to insure each wearing at the same rate to maintain the predetermined point gap at substantially the same distance throughout the life of the points.

Other objects are to provide ignition points which are relatively inexpensive and which are economical in use through eliminating cleaning and adjustment, which are simple in construction and yet efiicient to effect full current transfer and thereby insure trouble-free ignition, and which may be readily installed for replacement parts in presently constructed distributors, or which may be installed as initial parts in new distributors.

The foregoing and other objects and advantages are apparent from the foregoing description taken with the accompanying drawing, in which:

Fig. 1 is a side elevational view of a distributor incorporating ignition points including the teachings of the present invention, a part of the distributor case being broken away for clarity;

Fig. 2 is a side elevational view of the distributor and points of Fig. 1 rotated through ninety degrees, a part of the distributor case being broken away for clarity;

Fig. 3 is a plan view of the distributor and ignition points of Fig. 1, showing the ignition points in break position;

Fig. 4 is a view similar to Fig. 3, showing the ignition points in closed position;

Fig-5 is a side elevational view of the distributor rotor;

Fig. 6 is a cross-sectional view on substantially the line 66 of Fig. 5; and

Fig. 7 is an enlarged cross-sectional view through the roller mounted on the supporting shaft of the rotatable ignition point.

.Referring to the drawing more particularly by reference numerals, l0 indicates generally a distributor which incorporates the present novel ignition points assembly generally designated I2. The distributor includes the usual casing l4, rotatable shaft l5, plate I6 for mounting the elements of the ignition points assembly l2, and a rotor I! which is removably and adjustably connected to the shaft I5 by a setscrew H3.

The present ignition points assembly l2 comprises a pivoted ignition point l9 including a movable contact point 20 secured to the free end of an arm 2|, the other end of said arm 2] being formed as a loop 22 and being pivotally mounted on a post 23 supported on the plate I6. A spring member 24 is secured at one end by a rivet 25 to the arm 2| and is removably secured at the other end by a screw 26 to an upstanding flange 21 of a bracket 28 secured by suitable rivets 29 to the plate [6. Also secured to the arm 2| by the rivet 25 is a short spring arm 31, to the free end of which is secured a fibre rubbing block by a suitable rivet 33. A screw 35 threadedly engages a threaded aperture in the arm 2| and contacts at its free end the spring arm 3| for adjustably setting the position of the block 32 in respect to the rotor H, as is clear from the drawing.

The present ignition points assembly l2 also includes a rotatable ignition points 36 comprising a contact point 31 which is mounted on one end of a rotatable shaft 38 supported for rotation in suitable apertures formed in spaced flanges 39 upstanding from a bracket 40 secured by suitable screws 4| to the plate IS. The shaft 38 is maintained in an initial predetermined position of adjustment by a nut 43 adjacent the contact point 31 and an annular shoulder 44 formed integral with or secured to the other end thereof. No adjustment of the shaft 38 is made during use of the assembly I2. A roller 45 (Figs. 3 and 7) is mounted on the shaft 38 by means of a pin 46, or the like, which extends diametrically through the shaft 38 and on which the roller 45 is rotatably mounted, the pin 46 being peened over at its ends. The roller 45 extends upwardly from the shaft 33 and is disposed against the periphery of a cam member 41 secured to the top of the rotor IT. The cam member 41 is shown with a single cam 48, although more than one may be used. A tension spring 49 secured at one end to a post 50 mounted in the free end of the shaft 38 and at its other end to a bracket 51 secured to the plate M5 by a screw 52 biases the roller 45 into constant contact with the periphery of the cam member 41. A compression spring 55 disposed about the shaft 38 and bearing against one flange 39 and the pin 46 maintains the shaft 38 against longitudinal movement and with the nut 31 against its adjacent flange 39.

Operation The installation of the ignition points assembly l2 on the plate 16 of the distributor is manifest from the foregoing detailed description of the several elements thereof.

In order to insure substantially equal wear of the faces of the contact points 20 and 3! and the contacting edge of the block 32, the cam 45 is provided of a depth which will rotate the shaft 38-in'its contact-with the roll r 45 through a sufficient number of degrees in each rotation of the cam member 47 to wear the surfaces of the contact points 20 and 31 substantially the same amount as the block 32 is worn. This is a simple matter of adjustment as between materials and movement and can be readily ascertained.

With the ignition points assembly l2 mounted as shown in the drawings, rotation of the shaft l5 and the rotation therethrough of the rotor ll effects movement of the arm 2| through contact of the block 32 with the rotor ll. The spring arm 31 is biased into engagement with the screw 35 and the spring 24 urges the arm 2| and its supported elements clockwise about the post 23. The rotor ll' is octagonal, and, hence, th contact point 20 will make and break with the contact point 31 eight times during each revolution thereof.

During each revolution of the rotor I! and the cam member 41 secured thereto, the roller 45 will be moved outwardly by the cam 48 one time and returned. by the spring 49 to the position of Fig. 3. This displacement of the roller 45 effects rotation of the shaft 38 and the contactpoint 3'! secured thereto. During the engagement of the contact points 20 and 37, this rotation effects a frictional cleaning action which maintains the engaging surfaces smooth and bright and insures continued full-faced engagement thereof. oxidizing and pitting are eliminated and it is unnecessary to otherwise clean the faces of the contact points 20 and 31 during the life thereof. It is manifest that the depth of the cam 48 formed on the cammember-41 may be increased or decreased to respectively increase or decrease the arc of movement of the roller 45 and, hence, the shaft 38 and its contact point 31.

Hence, the labor involved in cleaning ignition points and the labor and cost of replacement parts involved in the replacement of ignition points is eliminated by the present construction. Furthermore, new point efficiency is maintained by the contact points 20 and 31 throughout the life of the present construction.

The spring mounting of the block 32 and the 1 provision of thescrew 35 permit ready adjust- 4 ment of the block 32 should it be necessary to move the block 32 outwardly from or nearer to the arm 2| to compensate for wear of the block 32 or the contact points 20 and 31, respectively.

It is manifest that there has been provided an ignition points assembly and cleaning method which fulfill all the objects and advantages sought therefor.

It is to be understood that the foregoing description and the accompanying drawing have been given by way of illustration and example. It is also to be understood that changes in form of the elements, rearrangement of parts and steps, andsubstitution of equivalent elements and steps, which will be obvious to those skilled in the art, are contemplated as within the scope of the present invention which is limited only by the claims which follow.

What is claimed is:

1. An ignition point assembly, comprising a pair of facing engageable contact points, means supporting one contact point for movement into and out of engagement with the other contact point, means supporting the other contact point for limited rotational movement, yieldable means urging rotation of said other contact point in one direction, and means for periodically rotating it less than 350 in the-opposite direction, so as to impart a rocking or oscillating movement to said other contact point, said last named means also actuating the supporting means of said one contact point.

2. An ignition point assembly, comprising a pair of facing engageable contact points, means supporting one contact point for movement into and out of engagement with the other con tact point, means supporting the other contact point for limited rotational-movement, cam means for rotating said other contact point less than 360 in one direcion for each revolution of the cam, and spring means urging it in the opposite direction, so as to impart a rocking oroscillating movement to said other contact point whereby the contact points are rubbed together once during each complete rotation of the cam means.

3. In an ignition point assembly, the combination of a shaft-like member mounted for limited rotational movement, a contact point secured to one end thereof, apost-like member extendingoutwardly from the shaft-like member, a coiled springhaving one end fastened to said post-like member so as to-urge rotation. of the shaft-like member in.one direction, a pin-like member secured tosaid shaft-like member, and cam means for. engagement with said pin-like memher for periodically rotating said shaft-like member less than 360 in the opposite direction.

4. In an ignition point assembly, the combination of a shaft-like member mounted for limited rotational movement; a first contact point at one end thereof; a second contact point pivotally mounted for movement into and out of engagement with the first contact point; a rotatably.

mounted member containing two separatecams on, a common. axis, one of said cams causing pivotal movement of the shaft-like member inone direction; yieldablemeans urging pivotal-movement thereof inthe oppositedirection; theother cam causing movement of the second contact away from the first contact; and yieldable means urging thesecondv contact toward the first ,con-

tact.

5. In an ignition point assembly-foruse with,

an internal combustion, engine containing a pre-y determined number of cylinders, the. combination of a shaft-like member mounted for limited rotational movement; a first contact point at one end thereof; a second contact point pivotally mounted for movement into and out of engagement with the first contact point; a rotatably mounted member containing two separate cams on a common axis, one of said cams causing pivotal movement of the shaft-like member in one direction once during each rotation of the rotatable member; yieldable means urging pivotal movement thereof in the opposite direction; the other cam causing movement of the second contact away from the first contact a number of times equal to the number of cylinders during each rotation of the rotatable member; and yieldable means urging the second contact toward the first contact.

SEBASTIAN HOFMANN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

